Rough running 1976/1979 2F, what am I missing? (1 Viewer)

[jm599]

Okay I'm pretty stupid with these things, but mine loped at idle until I changed cap and wires.
I was playing w my timing light moving the sensor to each plug wire and found what I guessed was poor spark to several. I was running rich too.

 

[fabiodaddy]

jm599,

Rig is running a new DUI electronic ignition (installed by PO), but could still have a problem I guess. When you had faulty spark you should have been able to to tell on the bad cylinders by looking at the plugs. Is that the case?

I'll have to check it out.

 

[jm599]

Can be intermittent firing, I think.
But "hot" higher voltage coils less prone to this.
I was sort of thinking that it was unlikely that several carbs were bad, and maybe some of the gas wasn't being burned.
Vacuum is okay now right? Just fluctuates?
My rigs often sit for 6 months during salty road season in damp containers.
That probably has something to do with my corrosion of cap and rotors and wires. It's first thing I look for lately.

Low power from clogged fuel filter took me awhile to discover once. Truck idled fine but would only go 30!
The gurus here have been invaluable to me.

 

[fabiodaddy]

Update. Finally solved my rough running issues. The solution was to toss the Chinese carbs (I tried three different ones and all had issues). I did what I originally planned to do and that was rebuild the original Aisin. Got the parts from Kurt and followed Pinheads videos (thanks Pinhead). Although mine was not identical to the carb in Pinheads videos, they still helped alot. Once I got it rebuilt and installed, the thing fired right up. I gave it a quick adjustment and it idles smoother that it ever has. Took it for a drive and now it doesn't stall at every stop light. Still need to finish the tune on it but runs pretty darn good now. Having some difficulty trying to figure out what to do with all of the vacuum ports on the carburetor though. It's a 1979 motor and carb, but PO(s) did a de-smog on it. Now I'm not sure what needs vacuum and what can be plugged off. Have not been able to find a 1979 vacuum/carburetor diagram yet. If anyone has any information about this please chime in.

 

[CHCP]

That's great news. I have a 78 2F, and had rough running issues and it turned out to be a hairline crack at the bottom of the aluminum intake manifold just below where the carb sits.

 

[DRYHEAT]

I realize I’m a few years late to this thread but here’s a vacuum diagram underneath the hood of my 79.

 

[65swb45]

I realize I’m a few years late to this thread but here’s a vacuum diagram underneath the hood of my 79.

Vvv

Doesn’t matter; that kind of tech is ALWAYS helpful. Thank you.

 

[DRYHEAT]

Thought I might add this sticker also, this is a March 1979 manufacture date. Originally sold in California.